Cars can have trailers, roof racks, and people can rent large cars for the short duration they need them. Breathless one-upmanship aside it’s not unreasonable to go to places with water, or for multiple people to bring water.

They literally won’t let us use water fountains right now. That’s for our own good. Wouldn’t want us getting the COVID!

bit strange to arrange a tournament in a place with no taps and no shops, but ok;

“On average, a professional water delivery service will charge anywhere from $175 to $380 per truckload., and the average truck will hold 6,000 gallons.” - https://www.howmuchisit.org/pool-water-delivery-cost/

Could buy a lot of those for the price of an SUV, especially sharing the price between all the people.

Inb4 the tournament is held on a remote mountain top inaccessible to tankers and hatchbacks alike and only accessible to 4x4s so there’s literally no other choice.

100 bottles? Are you coaching in the middle of the desert for a week? That's 20 bottles per person...

I coach a team of twelve.